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Online Markdown Viewer

Open .MD Files with Live Preview

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How to open and preview a Markdown file online

  1. 1

    Type or open a file

    Paste Markdown, choose a local .md, .markdown, or README file, or load a publicly accessible raw Markdown URL.

  2. 2

    Check the live preview

    Edit the source and review GFM tables, task lists, code highlighting, math, the table of contents, and Mermaid diagrams.

  3. 3

    Export or keep editing

    Download the Markdown, export or print the sanitized preview, or create a private fragment-only link to share the current content.

Features Overview

Open, edit, and read .md or README files online with live GFM, code block, math, and Mermaid previews, while all processing stays in your browser.

Tool Description

Open and preview .md and README files online with GFM, syntax highlighting, Mermaid, math, and local browser-only processing. No install or sign-up required.

Capabilities Checklist

  • Supports GitHub Flavored Markdown, task lists, tables, footnotes, and autolinks.
  • Uses Shiki for code highlighting and includes one-click copy for code blocks.
  • Markdown to PDF: export via browser print, keeping the rendered layout.
  • Markdown to HTML: export a standalone single file.
  • Mermaid rendering online: flowcharts and sequence diagrams draw right in the preview.
  • Online editor: edit on the left, live preview on the right, drafts stay local.
  • Supports KaTeX math, table of contents, one-click formatting, Markdown download, and private fragment sharing.
  • Does not parse embedded HTML by default, reducing XSS risk during preview and export.

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Related Guides

How to Open an .MD File on Windows, macOS, Mobile, or Online

Learn how to open .md and README.md files on Windows, macOS, iPhone, Android, or in an online Markdown viewer, with editing, export, and privacy guidance.

Markdown Online Preview Guide: GFM, Mermaid, Math, and Privacy

Preview Markdown online with a practical guide to GFM tables, tasks, code highlighting, Mermaid, KaTeX, HTML/PDF export, and the privacy boundaries of files and URLs.

Preview README.md Online: Check GFM Before You Commit to GitHub

Use this pre-commit README.md preview checklist for heading structure, GFM tables, tasks, code blocks, relative links, images, Mermaid, and mobile layout.

Frequently Asked Questions

Which files can this reader load?
Select Load File to choose a .md, .markdown, README, or plain text file. You can also paste content or import a publicly accessible raw URL, and it renders in your browser immediately. To compare ways of opening .md files on Windows, macOS, and mobile, see the guide on how to open an .MD file.
Can I use this tool as a README viewer?
Yes. It supports GitHub Flavored Markdown, including tables, task lists, strikethrough, autolinks, footnotes, and syntax-highlighted code blocks for reviewing README.md files.
Is this online Markdown reader free and does it require an account?
It is free to use and does not require an account for reading, editing, formatting, Mermaid, math, or HTML export.
Does this Markdown reader upload my content?
No. Previewing, formatting, Mermaid rendering, and exports run locally in the browser. Share links store content after the URL # fragment, which browsers do not send to our server.
Which Markdown syntax is supported?
The reader supports standard Markdown plus GFM tables, task lists, strikethrough, autolinks, footnotes, fenced code blocks, Mermaid diagrams, and KaTeX math.
How do I preview Mermaid diagrams in Markdown?
Create a fenced code block with the mermaid language and enter the diagram syntax. The preview renders the SVG locally with Mermaid strict security mode.
Can I export Markdown as a PDF?
Use Print or Save PDF to open the browser print dialog and choose Save as PDF, or export the standalone HTML and print it later.
Why is embedded HTML disabled by default?
Embedded HTML increases XSS risk. The tool shows raw HTML as text by default to avoid executing untrusted content during preview or export.